chore: update ai sdk to v6.0.5

[DIYgod]

Description

Update AI SDK to v6.0.5 and adjust tool UI helper usage to match the new API. Align Zod versions to satisfy AI SDK peer requirements.

PR Type

• Feature
• Bugfix
• Hotfix
• Other (please describe): Dependency update

Screenshots (if UI change)

Demo Video (if new feature)

Linked Issues

Additional context

Tests not run (not requested).

Changelog

• I have updated the changelog/next.md with my changes.

[vercel]

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Project	Deployment	Review	Updated (UTC)
follow	Building	Preview, Comment	Jan 1, 2026 7:51am
follow-external-ssr	Building	Preview, Comment	Jan 1, 2026 7:51am

[safedep]

SafeDep Report Summary

Package Details

Package	Malware	Vulnerability	Risky License	Report
@ai-sdk/gateway @ 2.0.7 pnpm-lock.yaml				🔗
@ai-sdk/gateway @ 3.0.4 pnpm-lock.yaml				🔗
@ai-sdk/provider @ 3.0.1 pnpm-lock.yaml				🔗
@ai-sdk/provider-utils @ 4.0.2 pnpm-lock.yaml				🔗
ai @ 5.0.88 pnpm-lock.yaml				🔗
ai @ 6.0.5 pnpm-lock.yaml apps/desktop/layer/renderer/package.json packages/internal/database/package.json packages/internal/shared/package.json				🔗
whatwg-encoding @ 3.1.1 pnpm-lock.yaml				🔗
zod @ 3.25.76 pnpm-lock.yaml apps/desktop/layer/renderer/package.json apps/mobile/package.json apps/ssr/package.json packages/internal/shared/package.json				🔗

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